Details

Ray
_Designed by YahooJAPAN ( http://www.thingiverse.com/thing:182258 )
_Ray, any of the cartilaginous fishes of the order Batoidei, related to sharks and placed with them in the class Chondrichthyes. The order includes 534 species.
Rays are distinguished from sharks by a flattened, disklike body, with the five gill openings and the mouth generally located on the underside. Rays are further distinguished from sharks by their greatly enlarged, winglike pectoral fins, which extend forward along the sides of the head above the gill openings. Many rays swim and breathe differently from sharks, propelling themselves with their pectoral fins and taking in water for respiration through large openings (spiracles) on the upper surface of the head, rather than through the mouth. The ray’s tail is generally long and slender and in many species bears one or more sharp, saw-edged, venomous spines that can be used to inflict painful wounds.
_Rays are predominantly marine and are found in all oceans. Many are slow-moving bottom dwellers. Manta rays feed on plankton and small animals; others take various fishes and invertebrates, sometimes damaging commercially valuable shellfish beds. Other than skates, most or possibly all rays bear living young. Fertilization is internal, the male introducing sperm into the female by means of special copulatory organs (claspers) that are the modified edges of the pelvic fins.
Rays can be classified into the following groups: electric rays, sawfishes, skates, and various families of rays that have slender, whiplike tails equipped with spines and that are all-inclusively called stingrays, or whip-tailed rays.About 20 species are known to inhabit warm seas, with some reaching a weight of 200 pounds (90 kg).
_The remaining rays comprise the suborder Myliobatoidei and consist of whip-tailed rays (family Dasyatidae), butterfly rays (Gymnuridae), stingrays (Urolophidae), eagle rays (Myliobatidae), manta rays (or devil rays; Mobulidae), and cow-nosed rays (Rhinopteridae). Common to the rays of all these families is a long, slender, whiplike tail that usually has a barbed spine connected with a poison gland; this spine is capable of inflicting serious wounds and is a dangerous weapon when the tail is lashed. Almost all of these rays are inhabitants of warm seas, except for a few species of stingray that live in the rivers of South America.